Molecules chilled below Doppler limit

August 29, 2017 by Bob Yirka, Phys.org report
Credit: CC0 Public Domain

A team of researchers working at the Centre for Cold Matter, Blackett Laboratory, Imperial College London, has found a way to chill molecules much closer to absolute zero. In their paper published in the journal Nature Physics, the team describes the two-step technique they used to achieve the feat and offer some ideas on how it might be used by others in the near future.

Scientist learned to chill atoms to near absolute zero some time ago, and have come as close as 50 trillionths of a degree in more recent times. But doing the same with molecules has remained elusive, until now. In this new effort, the researchers found that combining two traditional methods of cooling could be used to cool molecules to temperatures much closer to absolute zero than current methods, which typically bring molecules to just hundredths of degrees above absolute zero.

The researchers worked with calcium monofluoride molecules, using magnets to hold them in place and lasers to cool them by slowing them down—a technique that has been used widely in the past. To chill the molecules further (beyond the Doppler limit) the team used an adapted form of Sisyphus cooling, in which two lasers are fired directly at one another, creating an electromagnetic field. The field caused a constant exertion on the molecules, pulling energy from them, which cooled them. Using the combined methods, the researchers report that they were able to cool the molecules down to within 50 millionths of a degree above .

When scientists learned to chill atoms to similar temperatures, a flurry of subsequent research efforts sought to take advantage of a new way to study atomic properties. With a similar technique now at hand for molecules, it is likely that a similar research flurry will occur. Molecules at such a cold temperature have less movement, which should make them easier to study. It should also slow reactions, making it easier to see what actually occurs. It is also possible that researchers could learn more about the fundamentals of , especially regarding simultaneous molecular particle interactions.

Explore further: Laser cooling a polyatomic molecule

More information: S. Truppe et al. Molecules cooled below the Doppler limit, Nature Physics (2017). DOI: 10.1038/nphys4241

Related Stories

Laser cooling a polyatomic molecule

April 26, 2017

(Phys.org)—A team of researchers at Harvard University has successfully cooled a three-atom molecule down to near absolute zero for the first time. In their paper published in Physical Review Letters, the team describes ...

Direct laser cooling of molecules

October 21, 2010

Cooling molecules with lasers is harder than cooling individual atoms with lasers. The very process of laser cooling, in which atoms are buffeted by thousands of photons, was thought by many to be impossible for molecules ...

New way found to cool atoms and molecules

August 9, 2005

Physicists at The University of Texas say they've found a new technique for cooling atoms and molecules, allowing more effective quantum physics studies.

Scientists using lasers to cool and control molecules

September 20, 2010

(PhysOrg.com) -- Ever since audiences heard Goldfinger utter the famous line, “No, Mr. Bond; I expect you to die,” as a laser beam inched its way toward James Bond and threatened to cut him in half, lasers have been thought ...

Recommended for you

Walking crystals may lead to new field of crystal robotics

February 23, 2018

Researchers have demonstrated that tiny micrometer-sized crystals—just barely visible to the human eye—can "walk" inchworm-style across the slide of a microscope. Other crystals are capable of different modes of locomotion ...

Researchers turn light upside down

February 23, 2018

Researchers from CIC nanoGUNE (San Sebastian, Spain) and collaborators have reported in Science the development of a so-called hyperbolic metasurface on which light propagates with completely reshaped wafefronts. This scientific ...

Recurrences in an isolated quantum many-body system

February 23, 2018

It is one of the most astonishing results of physics—when a complex system is left alone, it will return to its initial state with almost perfect precision. Gas particles, for example, chaotically swirling around in a container, ...

Seeing nanoscale details in mammalian cells

February 23, 2018

In 2014, W. E. Moerner, the Harry S. Mosher Professor of Chemistry at Stanford University, won the Nobel Prize in chemistry for co-developing a way of imaging shapes inside cells at very high resolution, called super-resolution ...

Hauling antiprotons around in a van

February 22, 2018

A team of researchers working on the antiProton Unstable Matter Annihilation (PUMA) project near CERN's particle laboratory, according to a report in Nature, plans to capture a billion antiprotons, put them in a shipping ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.